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1.
Actas Dermosifiliogr ; 2024 May 23.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38795842

RESUMO

INTRODUCTION: A clinical dermatological research was conducted in Spain from 2005 through 2014 as part of the MaIND project with the provinces or centers with the highest number of published articles. However, a low level of evidence in scientific production was confirmed as the overall result. The aim of this study is to update the Spanish clinical dermatological research in bibliometric terms from 2015 through 2021 with comparisons between both periods of time. MATERIAL AND METHODS: We conducted a bibliometric study to replicate the methodology used in the article to be updated. We included articles whose corresponding authors' affiliation was a Spanish dermatological center, which met the criteria for clinical research in dermatology, including a level of evidence ≤4. RESULTS: A total of 1,674 out of the 10,199 articles met the inclusion criteria. An interactive map representing quantitative and qualitative indicators calculated for the 2005-2021 is presented here. In the study period, we found an increasing trend both in the number of published articles (P<.002) and in the mean number of citation-years per article (P<.01). A total of 22 of the articles had a level of evidence >4, with a positive trend towards more articles having a higher level of evidence (P<.03). ACTAS DERMOSIFILOGRÁFICAS still maintains its position as the journal with the highest number of articles received (18%, a total of 302 articles). CONCLUSIONS: The results of this study show that, in Spain, the scientific production of dermatology represents an upward trend in quantity, impact, and level of evidence.

2.
Actas Dermosifiliogr ; 2024 Jul 25.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-39067573

RESUMO

INTRODUCTION: Hidradenitis suppurativa (HS) is a chronic skin disease whose impact on skin homeostasis has not been adequately studied at present. Knowledge about how skin function changes in these patients, and could be of interest not only to improve the topical management of the disease, but also as an objective measure of disease activity. The aim of this study was to compare skin homeostasis and the epidermal barrier function in lesional and healthy skin areas of patients with HS. METHODS: We conducted a cross-sectional study. Skin homeostasis and the epidermal barrier function of lesions were assessed in HS patients using validated tools. A healthy perilesional skin control was assigned to each lesion to compare skin homeostasis parameters. RESULTS: A total of 43 patients were included: 22 nodules, 10 abscesses and 25 draining tunnels were measured. The male-to-female ratio was 20:23, and the mean age, 35.95 years (SD, 14.82). Increased transepidermal water loss (TEWL) and erythema were found in nodules, abscesses and draining tunnel vs healthy skin. A direct association was observed between inflammatory nodules TEWL and IHS4 stage. In draining tunnels, a direct association was observed between TEWL and smoking. A trend of increasing TEWL values was observed as a function of Hurley stage. CONCLUSION: HS lesions exhibit epidermal barrier dysfunction that depends on the severity of inflammatory activity. These results could be useful to develop objective classification systems for the severity and degree of involvement of HS or help in the development of vehicles for specific drugs, antiseptics and dressings for the management of this disease.

3.
Actas Dermosifiliogr ; 2024 May 18.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38768808

RESUMO

Spanish Autonomous Communities (ACs) are entitled to decide on the prescription requirements of their own territories, which can create inequalities in access to new drugs in the management of psoriasis. The objective of this study was to assess whether the level of restrictions in the access to new drugs for the management psoriasis was associated with the probability of achieving disease control measured using the Minimum Disease Activity (MDA) criteria. Therefore, we combined the results of 2 previous independent, cross-sectional studies: one that described the MDA in psoriasis by AC, and another that evaluated the level of restrictions to drug access by AC. We found that the higher the number of restrictions the lower the chances of achieving the MDA criteria (P=.013). Our results suggest that, in Spain, geographical differences in the access to new drugs may be creating health inequalities across the country.

4.
Actas Dermosifiliogr ; 115(3): 224-230, 2024 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37858857

RESUMO

BACKGROUND: The COVID-19 pandemic may have adversely affected the early diagnosis of skin cancer. OBJECTIVE: To compare epidemiological, clinical and histopathological characteristics in patients undergoing cutaneous squamous cell carcinoma (SCC) surgery before and after the beginning of the pandemic. MATERIAL & METHODS: We conducted a cross-sectional study including two case series: (1) patients operated on for SCC in the year after the first state of alarm in Spain (15 March 2020), and (2) patients with SCC operated on in the previous year. Epidemiological, clinical and histopathological variables, tumour stage and risk grade were collected. RESULTS: 248 patients were included (127 undergoing surgery before the pandemic and 121 after the pandemic). After the beginning of the pandemic, the percentage of high-risk SCC significantly increased from 35.3% to 46.2% (p=0.011). However, no significant differences were found in thickness, perineural invasion or metastases. CONCLUSIONS: Although there has not been a significant reduction in the number of SCC operated on after the pandemic, there has been a significant increase in high-risk SCC. All this could lead to an increase in skin cancer mortality in the future.


Assuntos
COVID-19 , Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Pandemias , COVID-19/epidemiologia , Estudos Transversais
5.
Actas Dermosifiliogr ; 115(3): T224-T230, 2024 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38185206

RESUMO

BACKGROUND: The COVID-19 pandemic may have adversely affected the early diagnosis of skin cancer. OBJECTIVE: To compare epidemiological, clinical and histopathological characteristics in patients undergoing cutaneous squamous cell carcinoma (SCC) surgery before and after the beginning of the pandemic. MATERIAL & METHODS: We conducted a cross-sectional study including two case series: (1) patients operated on for SCC in the year after the first state of alarm in Spain (15 March 2020), and (2) patients with SCC operated on in the previous year. Epidemiological, clinical and histopathological variables, tumour stage and risk grade were collected. RESULTS: 248 patients were included (127 undergoing surgery before the pandemic and 121 after the pandemic). After the beginning of the pandemic, the percentage of high-risk SCC significantly increased from 35.3% to 46.2% (p=0.011). However, no significant differences were found in thickness, perineural invasion or metastases. CONCLUSIONS: Although there has not been a significant reduction in the number of SCC operated on after the pandemic, there has been a significant increase in high-risk SCC. All this could lead to an increase in skin cancer mortality in the future.


Assuntos
COVID-19 , Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Pandemias , COVID-19/epidemiologia , Estudos Transversais
6.
Actas Dermosifiliogr ; 115(3): 231-236, 2024 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37884261

RESUMO

BACKGROUND AND OBJECTIVE: Quality of professional life (QPL) is defined as a sense of well-being derived from a balance between the challenges of work and the resources available to deal with them. Impaired QPL can contribute to burnout. The aim of this study was to evaluate QPL in Spanish dermatologists using a validated questionnaire. MATERIAL AND METHODS: We designed a cross-sectional study in which Spanish dermatologists were invited to complete an online questionnaire sent out by messaging applications. The dermatologists were asked to provide sociodemographic information, answer 3 open questions, and complete the 35-item Spanish QPL questionnaire (Spanish abbreviation, CVP-35). RESULTS: We analyzed the information submitted by 106 dermatologists (62 women, 58%) with a mean age of 41 years (95% CI, 43.3-38.8 years). Women and department heads scored significantly higher in the workload domain of the questionnaire (P=.02 and P=.005, respectively). A heavy caseload was mentioned as the main factor contributing to impaired QPL and the main change in the wake of the COVID-19 pandemic. CONCLUSIONS: Female dermatologists reported heavier workloads. Heavy caseloads and more remote work were the main changes identified after the COVID-19 pandemic. Heavy caseloads have a significant impact on the QPL of dermatologists in Spain. Reducing caseloads would improve general job satisfaction and quality of care provision.


Assuntos
Esgotamento Profissional , COVID-19 , Humanos , Feminino , Adulto , Dermatologistas , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Satisfação no Emprego , Inquéritos e Questionários , Esgotamento Profissional/epidemiologia
7.
Actas Dermosifiliogr ; 2024 Aug 03.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-39102977

RESUMO

Spanish Autonomous Communities (ACs) are entitled to decide on the prescription requirements of their own territories, which can create inequalities in access to new drugs in the management of psoriasis. The objective of this study was to assess whether the level of restrictions in the access to new drugs for the management psoriasis was associated with the probability of achieving disease control measured using the Minimum Disease Activity (MDA) criteria. Therefore, we combined the results of 2 previous independent, cross-sectional studies: one that described the MDA in psoriasis by AC, and another that evaluated the level of restrictions to drug access by AC. We found that the higher the number of restrictions the lower the chances of achieving the MDA criteria (p = 0.013). Our results suggest that, in Spain, geographical differences in the access to new drugs may be creating health inequalities across the country.

8.
Actas Dermosifiliogr ; 115(3): 237-245, 2024 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37890617

RESUMO

BACKGROUND: Although the Spanish Ministry of Health prepares national therapeutic positioning reports (TPRs) and drug reimbursement policies, each of the country's 17 autonomous communities (ACs) is responsible for health care services and prescription requirements in its territory. The aim of the EQUIDAD study was to describe and explore potential differences in prescription requirements for new dermatology drugs across the autonomous communities. MATERIAL AND METHODS: Cross-sectional study conducted in April and May, 2023. Two dermatologists with management responsibilities from each autonomous community reported on territorial and more local prescription requirements for drugs covered by national TPRs issued between 2016 and 2022. RESULTS: Thirty-three researchers from 17 autonomous communities participated. The data submitted revealed between-community inequities in access to new drugs. Overall, 64.7% of the regions imposed additional prescription requirements to those mentioned in the TPRs for psoriasis. This percentage was lower for atopic dermatitis (35.3%) and melanoma (11.8%). The most common requirement for accessing a new drug was a previous prescription for another drug. Differences and additional requirements were also detected at the local level (i.e., differences between hospitals within the same autonomous community). CONCLUSIONS: Spain's autonomous communities have multiple regional and local prescription requirements that are not aligned with national TPR recommendations. These differences result in inequitable access to new drugs for both patients and practitioners across Spain.


Assuntos
Dermatologia , Humanos , Espanha , Estudos Transversais
9.
Actas Dermosifiliogr ; 115(3): T237-T245, 2024 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38242435

RESUMO

BACKGROUND: Although the Spanish Ministry of Health prepares national therapeutic positioning reports (TPRs) and drug reimbursement policies, each of the country's 17 autonomous communities (ACs) is responsible for health care services and prescription requirements in its territory. The aim of the EQUIDAD study was to describe and explore potential differences in prescription requirements for new dermatology drugs across the autonomous communities. MATERIAL AND METHODS: Cross-sectional study conducted in April and May, 2023. Two dermatologists with management responsibilities from each autonomous community reported on territorial and more local prescription requirements for drugs covered by national TPRs issued between 2016 and 2022. RESULTS: Thirty-three researchers from 17 autonomous communities participated. The data submitted revealed between-community inequities in access to new drugs. Overall, 64.7% of the regions imposed additional prescription requirements to those mentioned in the TPRs for psoriasis. This percentage was lower for atopic dermatitis (35.3%) and melanoma (11.8%). The most common requirement for accessing a new drug was a previous prescription for another drug. Differences and additional requirements were also detected at the local level (i.e., differences between hospitals within the same autonomous community). CONCLUSIONS: Spain's autonomous communities have multiple regional and local prescription requirements that are not aligned with national TPR recommendations. These differences result in inequitable access to new drugs for both patients and practitioners across Spain.


Assuntos
Dermatologia , Humanos , Espanha , Estudos Transversais
12.
Plant Sci ; 232: 13-22, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25617319

RESUMO

This work aims to characterize the physiological response of grapevine (Vitis vinifera L.) cv. Tempranillo to UV-B radiation under water deficit conditions. Grapevine fruit-bearing cuttings were exposed to three levels of supplemental biologically effective UV-B radiation (0, 5.98 and 9.66kJm(-2)day(-1)) and two water regimes (well watered and water deficit), in a factorial design, from fruit-set to maturity under glasshouse-controlled conditions. UV-B induced a transient decrease in net photosynthesis (Anet), actual and maximum potential efficiency of photosystem II, particularly on well watered plants. Methanol extractable UV-B absorbing compounds (MEUVAC) concentration and superoxide dismutase activity increased with UV-B. Water deficit effected decrease in Anet and stomatal conductance, and did not change non-photochemical quenching and the de-epoxidation state of xanthophylls, dark respiration and photorespiration being alternative ways to dissipate the excess of energy. Little interactive effects between UV-B and drought were detected on photosynthesis performance, where the impact of UV-B was overshadowed by the effects of water deficit. Grape berry ripening was strongly delayed when UV-B and water deficit were applied in combination. In summary, deficit irrigation did not modify the adaptive response of grapevine to UV-B, through the accumulation of MEUVAC. However, combined treatments caused additive effects on berry ripening.


Assuntos
Raios Ultravioleta , Vitis/efeitos da radiação , Clorofila/metabolismo , Dessecação , Peroxidação de Lipídeos/efeitos da radiação , Fotossíntese/efeitos da radiação , Estômatos de Plantas/efeitos da radiação , Superóxido Dismutase/metabolismo , Vitis/metabolismo , Vitis/fisiologia , Água/metabolismo
13.
Plant Sci ; 236: 168-76, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26025530

RESUMO

The increase in grape berry ripening rates associated to climate change is a growing concern for wine makers as it rises the alcohol content of the wine. The present work studied the combined effects of elevated CO2, temperature and UV-B radiation on leaf physiology and berry ripening rates. Three doses of UV-B: 0, 5.98, 9.66 kJm(-2)d(-1), and two CO2-temperature regimes: ambient CO2-24/14 °C (day/night) (current situation) and 700 ppm CO2-28/18 °C (climate change) were imposed to grapevine fruit-bearing cuttings from fruit set to maturity under greenhouse-controlled conditions. Photosynthetic performance was always higher under climate change conditions. High levels of UV-B radiation down regulated carbon fixation rates. A transient recovery took place at veraison, through the accumulation of flavonols and the increase of antioxidant enzyme activities. Interacting effects between UV-B and CO2-temperature regimes were observed for the lipid peroxidation, which suggests that UV-B may contribute to palliate the signs of oxidative damage induced under elevated CO2-temperature. Photosynthetic and ripening rates were correlated. Thereby, the hastening effect of climate change conditions on ripening, associated to higher rates of carbon fixation, was attenuated by UV-B radiation.


Assuntos
Dióxido de Carbono/metabolismo , Mudança Climática , Raios Ultravioleta , Vitis/fisiologia , Carbono/metabolismo , Frutas/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Temperatura , Vitis/efeitos da radiação
14.
J Plant Physiol ; 116(4): 285-92, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-23195298

RESUMO

Plants of alfalfa (Medicago sativa L.) were subjected to six levels of nitrate ranging from 0 to 200 mM. Then, nodule content of soluble protein and activities of the nodule enzymes, nitrogenase (C(2)H(2) reduction activity), glutamine synthetase (EC 6.3.1.2), glutamate synthase (EC 1.4.1.14), and NADH/NAD(+)-glutamate dehydrogenases (EC 1.4.1.2) were determined. Decline of glutamate synthase activity closely paralleled that of nitrogenase. In contrast, glutamine synthetase activity reached a minimum at 20mM nitrate but began to recover at higher nitrate concentrations. Patterns of NADH-(aminating) and NAD(+)-(deaminating) glutamate dehydrogenase activities were opposed with a great increase (2- to 5-fold) in the aminating direction at highest levels of nitrate. Results indicate a main role of glutamine synthetase/glutamate synthase pathway in the assimilation of fixed N. In addition, increase of the activities of glutamine synthetase and NADH-glutamate dehydrogenase concomitant with an almost fully suppressed nitrogenase and decreased NAD(+)-glutamate dehydrogenase activities at above 20mM nitrate reflect: (a) rapid induced senescence of nodules and (b) the production of ammonia by alternative means as nitrate reduction or oxidative deamination of amino acids.

15.
Gac Sanit ; 9(48): 159-65, 1995.
Artigo em Espanhol | MEDLINE | ID: mdl-7558628

RESUMO

Based on cases reported to the National AIDS Register by end June 1994, we analysed changes in the epidemiological pattern of AIDS in Spain for the periods 1981-1989 and 1990-1992. Cases diagnosed in 1981-1989 were mainly males (83.1%), subjects under 30 years of age (55.9%), and intravenous drug users (63.8%) or homo/bisexual males (16.8%). In 1990-1992 there was an increase in the proportion of females (18.5%), cases older than 29 (55.0%), and mean age diagnosis. Proportions of homo/bisexual, blood components recipients, and mother-to-child transmission decreased, while heterosexual transmission increased from 4.3% to 8.0%. In spite of large inter-regional differences in 1981-1989, some regions, such as La Rioja, Navarre, Murcia, Galicia and Aragon, rose more than Spain as a whole. Although the epidemiological pattern in both periods is similar, significant and independent changes in analysed variables are to be observed.


Assuntos
Síndrome da Imunodeficiência Adquirida/epidemiologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Espanha/epidemiologia , Fatores de Tempo
16.
Plant Sci ; 226: 22-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25113447

RESUMO

Continued emissions of CO2, derived from human activities, increase atmospheric CO2 concentration. The CO2 rise stimulates plant growth and affects yield quality. Effects of elevated CO2 on legume quality depend on interactions with N2-fixing bacteria and mycorrhizal fungi. Growth at elevated CO2 increases photosynthesis under short-term exposures in C3 species. Under long-term exposures, however, plants generally acclimate to elevated CO2 decreasing their photosynthetic capacity. An updated survey of the literature indicates that a key factor, perhaps the most important, that characteristically influences this phenomenon, its occurrence and extent, is the plant source-sink balance. In legumes, the ability of exchanging C for N at nodule level with the N2-fixing symbionts creates an extra C sink that avoids the occurrence of photosynthetic acclimation. Arbuscular mycorrhizal fungi colonizing roots may also result in increased C sink, preventing photosynthetic acclimation. Defoliation (Anthyllis vulneraria, simulated grazing) or shoot cutting (alfalfa, usual management as forage) largely increases root/shoot ratio. During re-growth at elevated CO2, new shoots growth and nodule respiration function as strong C sinks that counteracts photosynthetic acclimation. In the presence of some limiting factor, the legumes response to elevated CO2 is weakened showing photosynthetic acclimation. This survey has identified limiting factors that include an insufficient N supply from bacterial strains, nutrient-poor soils, low P supply, excess temperature affecting photosynthesis and/or nodule activity, a genetically determined low nodulation capacity, an inability of species or varieties to increase growth (and therefore C sink) at elevated CO2 and a plant phenological state or season when plant growth is stopped.


Assuntos
Aclimatação , Biomassa , Mudança Climática , Medicago sativa/crescimento & desenvolvimento , Fotossíntese , Medicago sativa/metabolismo , Nitrogênio/metabolismo
17.
Plant Sci ; 226: 30-40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25113448

RESUMO

Human activities are increasing atmospheric CO2 concentration and temperature. Related to this global warming, periods of low water availability are also expected to increase. Thus, CO2 concentration, temperature and water availability are three of the main factors related to climate change that potentially may influence crops and ecosystems. In this report, we describe the use of growth chamber - greenhouses (GCG) and temperature gradient greenhouses (TGG) to simulate climate change scenarios and to investigate possible plant responses. In the GCG, CO2 concentration, temperature and water availability are set to act simultaneously, enabling comparison of a current situation with a future one. Other characteristics of the GCG are a relative large space of work, fine control of the relative humidity, plant fertirrigation and the possibility of light supplementation, within the photosynthetic active radiation (PAR) region and/or with ultraviolet-B (UV-B) light. In the TGG, the three above-mentioned factors can act independently or in interaction, enabling more mechanistic studies aimed to elucidate the limiting factor(s) responsible for a given plant response. Examples of experiments, including some aimed to study photosynthetic acclimation, a phenomenon that leads to decreased photosynthetic capacity under long-term exposures to elevated CO2, using GCG and TGG are reported.


Assuntos
Mudança Climática , Ecologia/métodos , Ecologia/instrumentação , Plantas/metabolismo , Temperatura
18.
Phytochemistry ; 102: 106-14, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24713570

RESUMO

Grapevine cv. Tempranillo fruit-bearing cuttings were exposed to supplemental ultraviolet-B (UV-B) radiation under controlled conditions, in order to study its effect on grape traits, ripening, amino acids and flavonoid profile. The plants were exposed to two doses of UV-B biologically effective (5.98 and 9.66kJm(-2)d(-1)), applied either from fruit set to ripeness or from the onset of veraison to ripeness. A 0kJm(-2)d(-1) treatment was included as a control. UV-B did not significantly modify grape berry size, but increased the relative mass of berry skin. Time to reach ripeness was not affected by UV-B, which may explain the lack of changes in technological maturity. The concentration of must extractable anthocyanins, colour density and skin flavonols were enhanced by UV-B, especially in plants exposed from fruit set. The quantitative and qualitative profile of grape skin flavonols were modified by UV-B radiation. Monosubstituted flavonols relative abundance increased proportionally to the accumulated UV-B doses. Furthermore, trisubstituted forms, which where predominant in non-exposed berries, were less abundant as UV-B exposure increased. Although total free amino acid content remained unaffected by the treatments, the increased levels of gamma-aminobutyric acid (GABA), as well as the decrease in threonine, isoleucine, methionine, serine and glycine, revealed a potential influence of UV-B on the GABA-mediated signalling and amino acid metabolism. UV-B had an overall positive impact on grape berry composition.


Assuntos
Aminoácidos/química , Flavonoides/química , Frutas/química , Raios Ultravioleta , Vitis/química
19.
Plant Sci ; 213: 114-22, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24157214

RESUMO

The present study aimed at evaluating the short- and long-term effects of UV-B radiation on leaves of grapevine Vitis vinifera (cv. Tempranillo). Grapevine fruit-bearing cuttings were exposed to two doses of supplemental biologically effective UV-B radiation (UV-BBE) under glasshouse-controlled conditions: 5.98 and 9.66kJm(-2)d(-1). The treatments were applied either for 20d (from mid-veraison to ripeness) or 75d (from fruit set to ripeness). A 0kJm(-2)d(-1) UV-B treatment was included as control. The main effects of UV-B were observed after the short-term exposure (20d) to 9.66kJm(-2)d(-1). Significant decreases in net photosynthesis, stomatal conductance, sub-stomatal CO2 concentration, the actual photosystem II (PSII) efficiency, total soluble proteins and de-epoxidation state of the VAZ cycle were observed, whereas the activities of several antioxidant enzymes increased significantly. UV-B did not markedly affect dark respiration, photorespiration, the maximum potential PSII efficiency (Fv/Fm), non-photochemical quenching (NPQ), as well as the intrinsic PSII efficiency. However, after 75d of exposure to 5.98and 9.66kJm(-2)d(-1) UV-B most photosynthetic and biochemical variables were unaffected and there were no sign of oxidative damage in leaves. The results suggest a high long-term acclimation capacity of grapevine to high UV-B levels, associated with a high accumulation of UV-B absorbing compounds in leaves, whereas plants seemed to be tolerant to moderate doses of UV-B.


Assuntos
Aclimatação/efeitos da radiação , Antioxidantes/metabolismo , Proteínas de Plantas/metabolismo , Vitis , Antioxidantes/análise , Dióxido de Carbono/metabolismo , Carotenoides/análise , Carotenoides/metabolismo , Respiração Celular/efeitos da radiação , Clorofila/análise , Clorofila/metabolismo , Peroxidação de Lipídeos/efeitos da radiação , Oxirredução/efeitos da radiação , Fotossíntese/efeitos da radiação , Complexo de Proteína do Fotossistema II/efeitos da radiação , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/análise , Estômatos de Plantas/fisiologia , Estômatos de Plantas/efeitos da radiação , Transpiração Vegetal/efeitos da radiação , Fatores de Tempo , Raios Ultravioleta , Vitis/fisiologia , Vitis/efeitos da radiação
20.
J Plant Physiol ; 168(17): 2007-14, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21880395

RESUMO

Future climatic conditions, including rising atmospheric CO(2) and temperature may increase photosynthesis and, consequently, plant production. A larger knowledge of legume performance under the predicted growth conditions will be crucial for safeguarding crop management and extending the area under cultivation with these plants in the near future. N(2) fixation is a key process conditioning plant responsiveness to varying growth conditions. Moreover, it is likely to increase under future environments, due to the higher photosynthate availability, as a consequence of the higher growth rate under elevated CO(2). However, as described in the literature, photosynthesis performance is frequently down-regulated (acclimated) under long-term exposure to CO(2), especially when affected by stressful temperature and water availability conditions. As growth responses to elevated CO(2) are dependent on sink-source status, it is generally accepted that down-regulation occurs in situations with insufficient plant C sink capacity. Alfalfa management involves the cutting of shoots, which alters the source-sink relationship and thus the photosynthetic behaviour. As the growth rate decreases at the end of the pre-cut vegetative growth period, nodulated alfalfa plants show photosynthetic down-regulation, but during regrowth following defoliation, acclimation to elevated CO(2) disappears. The shoot harvest also leads to a drop in mineral N uptake and C translocation to the roots, resulting in a reduction in N(2) fixation due to the dependence on photosynthate supply to support nodule function. Therefore, the production of new shoots during the first days following cutting requires the utilization of reduced C and N compounds that have been stored previously in reserve organs. The stored reserves are mediated by phytohormones such as methyl jasmonate and abscisic acid and in situations where water stress reduces shoot production this potentially enables the enhancement of taproot protein levels in nodulated alfalfa, which may lead to these plants being in better condition in the following cut/regrowth cycle. Furthering our knowledge of legume performance under predicted climate change conditions will be crucial for the development of varieties with better adaptation that will achieve greater and more efficient production values. Furthermore, for this purpose it will be necessary to improve existing methodologies and create new ones for phenotype characterization. Such knowledge will provide key information for future plant breeding programs.


Assuntos
Dióxido de Carbono/metabolismo , Medicago sativa/fisiologia , Fixação de Nitrogênio/fisiologia , Fotossíntese/fisiologia , Raízes de Plantas/fisiologia , Aclimatação , Biomassa , Mudança Climática , Regulação para Baixo/fisiologia , Temperatura Alta , Medicago sativa/crescimento & desenvolvimento , Nitrogênio/metabolismo , Raízes de Plantas/crescimento & desenvolvimento
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